Iran announced Monday that it has built its first ballistic missile silos, airing video of one of the facilities as it began a new round of military exercises.

The hardened, underground launch sites will allow Iranian commanders to fire missiles more quickly, Iran’s state-run Press TV reported. A military statement carried by the official Islamic Republic News Agency said the silos were capable of launching long-range missiles.

The announcement came as the Islamic republic opened a new round of war games, dubbed “Great Prophet 6.” Iran is expected to test-fire several types of missiles during the exercise, state news agencies reported.

Iran’s development of missile and nuclear fuel technology has led to U.N. sanctions and accusations from the United States that the clerical regime is trying to develop nuclear weapons.